architecture

Architecture

Is made of three modules that communicate via TCP/IP.

little sister core

The kernel needs no additional memory, makes no disk IO and forks no additional processes after it was successfully started. It holds the current status of all monitored systems. It knows which little sister helpers work for it. The kernel should be a super stable program.
The kernel is initialized by a configuration file and starts / connects to its little sister helpers for persistence, instruments and process scheduling.
The kernel gets status messages from its helpers.

little sister helper

Can make disk IO and connect to a database. Are steered by the little sister core. Send status and result messages to the kernel. Have a health status.

• measure http connections (get HTML response, response time)
• measure DB properties (table size, response times)
• file system monitoring (numer of files, size of files, file content change)
• process scheduling (via process pool)
• persist indicators, properties and messages (for example in a database)
• create log files

little sister web

Shows the status of all monitored systems. Asks the little sister core for this. Uses comet technology for updating status changes.
Can also show the history of status and indicator changes. (Calls core and gets helper that can answer that question.)
Can also administrate the kernel (new measure points, configuration changes, etc.)